This is hardly the time of year for picnics on the lawn, but I have nevertheless had a week dominated by Glyndebourne. First I went to London to see David Hare’s play The Moderate Soprano, about the creation of the Glyndebourne opera festival by John Christie in 1934; and then to a Glyndebourne production in Milton Keynes of Mozart’s opera Die Entführung aus dem Serail.